Dense Wavelength Division Multiplexing

Abstract : Seminar : ppt A DWDM terminal multiplexer. The multiplexer device actually contains a transponder wavelength conversion for each wavelength of the signal is. conversion wavelength transponders to receive optical input signal (ie, from a client layer SONET / SDH or other signal), converts this signal into the electrical domain, and retransmit the signal of 1,550 nm laser band. (DWDM systems contained 4 or 8 wavelength transponders convert to mid 1990. In 2000 or so, commercial systems capable of carrying 128 signals available.) Multiplexer terminal also contains an optical multiplexer, which is different from 1550 nm band signals and places them in a single fiber (eg fiber SMF-28). The terminal multiplexer may or may not support a local EDFA for optical signal power amplifier multi-wavelength. A DWDM terminal demultiplexer. The terminal demultiplexer breaks the multi-signal wavelength into individual signals and outputs on the fibers separate systems for client-layer (eg SONET / SDH) to register. Originally, this demultiplexing performed entirely passively, except for telemetry, as most of SONET systems can receive signals from 1550-nm. But to allow the transmission to remote client-layer (and allow the determination of domain digital signal integrity) such demultiplexed signals are usually sent to O / I / O output transponders prior to being sent to their systems customer-base. Often, the functionality of transponder output has been integrated into the input of the transponder so that most commercial systems have transponders that support bi-directional interface on both 1550-nm (inner) side, and external ( ie client-cons).